Indulgent toasted marshmallow and rhubarb cake

This delicious, one-of-a-kind cake was shared with Starts at 60 by the cooking queen herself: Nigella Lawson! The recipe is an extract from her book Cook, Eat, Repeat, which features a series of ingredients, recipes and personal stories from one of the best in the business. And if this cake is anything to go off, you’re in for a treat with this cookbook!

The mouthwatering toasted marshmallow and rhubarb are guaranteed people-pleasers, but you will need a blowtorch and some elbow grease to properly perfect this, so make sure you keep out of harm’s way by putting the cake on a heatproof stand in the final steps.

Ingredients

Rhubarb layer

• 400g pink forced rhubarb (trimmed weight)
• 100g caster sugar

Cake

• 6 large eggs, at room temperature
• 1 lemon
• 100ml full-fat milk, at room temperature
• 25g cornflour
• 100g plain flour
• 2 tsp baking powder
• 1⁄2 tsp bicarbonate of soda
• 1⁄4 tsp fine sea salt
• 150g caster sugar
• 150ml vegetable oil, plus more for greasing

Icing

• 6 egg whites, from eggs above
• 350g caster sugar
• 1⁄4 tsp fine sea salt
• 1⁄2 tsp cream of tartar or 1⁄2 tsp lemon juice
• 2 tsp vanilla extract

Method

1. Start by cooking the rhubarb. Heat the oven to 200C/180C fan forced. Cut trimmed rhubarb ribs into 5cm lengths if slender, 21⁄2cm if chunky. Put into an ovenproof dish in which they will more or less be able to sit in a single layer (I use a 20 x 26cm Pyrex dish) and sprinkle over the 100g of sugar. Mix together with your hands, leaving the rhubarb in a single layer as much as possible, then cover the dish with foil, sealing the edges well, and cook in the oven for approximately 30 minutes until the rhubarb is tender but still holding its shape.
2. Remove the foil and leave the dish of rhubarb out on the counter, watching it glow ever more pink as it cools. Turn the oven down to 170C/150C fan forced. Line the bottoms of two 20cm loose-bottomed sandwich tins and lightly grease the sides.
3. Separate the eggs, dropping the whites into a large mixing bowl or bowl of a freestanding mixer (whichever bowl you’re using should be thoroughly washed and grease-free) and the yolks into another. Cover the bowl of whites with food wrap and put to one side while you mix and bake the cake.
4. Finely grate the zest of the lemon and add to the bowl of yolks. Measure out the milk, juice the lemon and add 2 tablespoons of juice to the milk, and leave to stand for a minute. Mix together the cornflour, flour, baking powder, bicarbonate of soda and salt, and set this aside for now, too.
5. Add the 150g of sugar and the oil to the yolks and whisk on medium-high speed for 3 minutes, by which time the mixture will be rich, gleaming and billowy. Actually, it looks rather like a glorious mayonnaise.
6. Still whisking but slightly more slowly now, gently pour and scrape in the now curdled milk and, once it’s in, carry on whisking until combined (the mixture looks like custard at this stage). Finally, whisking more gently now, gradually spoon in the dry ingredients. Once in, use a spatula to scrape down the sides and fold everything gently together before dividing the airy mixture between the prepared tins.
7. Bake for 20–25 minutes, by which time the cakes will have risen up extravagantly, the tops a golden brown; they will feel soft and puffy to the touch but a cake tester should come out clean. Remove to a wire rack and let the cakes cool in their tins for 15 minutes – sinking a little as they do so – before very carefully turning out. You’ll need to loosen the edges with a small offset spatula first. These are tender sponges, so don’t rush or be rough. Once unmoulded, gently pull back and remove the lining papers straight away.
8. When the cakes are completely cold – which will take about an hour – you can get on with the icing. But first, tear off four strips of baking parchment, scrunch them, then unscrunch them and lay them flat to make the outline of a square on top of a cake stand. (This is to stop you covering the cake stand with sticky marshmallow icing later. It may sound like a hassle, but I wouldn’t advise you to leave out this step.) Place one of the cakes on it, top-side down, the paper strips under the edges. Also, now’s the time to lift the rhubarb pieces out of their syrup in the tin and on to a plate.
9. So, to the icing: get out a tall pan that you can sit your big bowl o’ whites on (without the bottom of the bowl touching the water) and heat a little water in it until just about to come to a simmer. Mix the 350g of sugar, salt and cream of tartar (or lemon juice) together and add to the egg whites. Then sit the mixing bowl on top of the pan, so it’s gently warmed by the barely simmering water underneath and, using a balloon whisk (thoroughly washed and grease-free, again), keep whisking for 3 minutes to dissolve the sugar. I couldn’t say this is hard to do but you can really feel it in your forearm. I’m always grateful when my 3-minute timer goes off!
10. Once the sugar’s dissolved and you have a smooth opaque mixture that’s warm to the touch, remove the bowl from the saucepan. Whisk at high speed for 5 minutes in a freestanding mixer, or for 6–7 minutes if using an electric handheld whisk, by which time the whites will be very, very thick and ludicrously voluminous. Whisk in 1 teaspoon of the vanilla extract, and when it’s incorporated, whisk in the remaining teaspoon, then give a good fold by hand to make sure every bit is mixed in.
11. Dollop a generous amount of marshmallow icing onto the waiting cake and smooth right to the edges so that you have a layer about 1cm thick (this should use about a quarter of the icing). Cover this with the rhubarb, though leave about 1⁄2cm perimeter around the edge; I go slowly here, using a couple of dessertspoons to ferry the rhubarb to the cake. And you might want to tilt the rhubarb plate away from you slightly as you transfer the slices, to make sure you leave any pooling liquid behind.
12. Top with the second cake, right way up, and use just under half the icing left in the bowl to cover the top, going just beyond the edges. Then carefully spread the rest of the icing thickly around the sides – leaving a tiny bit in the mixing bowl – until the whole cake is completely covered. Now for the really fun part: dip your fingers in the bit of icing left in the bowl and then dab the top and sides of the cake, lightly pulling up and teasing out spikes of marshmallow icing (I feel like an ’80s hairdresser doing this). Bear in mind that sometimes, as you do the sides, you will pull bits of the icing off, leaving a hole, but don’t panic, just pat it back on. Gently pull out the strips of paper from beneath the cake and discard, then seal the bottom of the cake with any remaining icing should you need to. Then, slightly dampen a piece of kitchen towel with cold water, and rub off any stray bits of icing or sugar smear from the plate.
13. Carefully take the cake somewhere you can kindle fire safely. Light a blowtorch and, holding it fairly near the cake and with not too timorous a flame, toast the top and the sides of the icing.
14. I find this cake easiest to slice if left to stand for a couple of hours before serving. And you need to slice generously, as with all layer cakes.